[aprssig] EF Johnson Offering Mike With Built-In Display GPS And APRS-like Functions

Scott Miller scott at opentrac.org
Tue Jan 27 17:29:15 EST 2009

The same thing is sold by GISteq and Infinity Gear, and I think Pryme as 
well.  They all seem to claim that it's their own product, but I have 
yet to discover who really makes it.  If I go back to Hong Kong in April 
I'll see if I can find it there, though Taiwan's probably more likely.

It uses 1200 bps MSK, generated by a CML CMX469A modem chip.  I grabbed 
some sample data from a GISteq unit that someone was nice enough to lend me.

It's not directly useful for APRS, but I did reverse engineer part of 
the proprietary NMEA sentence it puts out (in my hotel room, during 
SARCity last October), and the development build of the Tracker2 
firmware will produce it now.  This has no direct relevance for the GPS 
mic, but it means you can use the ArcGIS plug-in that was built for them 
to do APRS.  In a very clunky way, for the version I tested.  Maybe 
there's something out there with better integration.


Stephen H. Smith wrote:
> APRS entirely inside a hand mic?
> New product announcement in the publication formerly known as "MRT" 
> (Mobile Radio Technology) and now as "Urgent Communications". This 
> sounds like the ultimate Mic-E setup -- inside the mic. Photo makes it 
> look like a basic eTrex or even a HamHud (it does test messaging) 
> stuffed inside a hand mic, From Johnson's website at:
> <http://www.efjohnsontechnologies.com/products/portables/speaker_mic>
> "The new Discover™ GPS Speaker Microphone is excellent for coordinating 
> field operations and seeing the location of group members in real time. 
> A large, backlit LCD screen provides an easy to use icon-based operation 
> and allows for graphic representation of relative distance and direction 
> to other team members. Send text messages and waypoints to groups, 
> individuals or dispatch. Transmit highly accurate location data in a 
> variety of ways: over analog or digital channels, clear or encrypted, 
> with every push-to-talk or at pre-determined time or distance intervals."
> A bit pricey at $500 a pop though. Perhaps Scott or Byon could cram 
> their respective two-way trackers and a GPS module into a similar mic 
> case. Maybe even with a POCSAG decoder in firmware..........
> ------------------------------------------------------------------------
> --
> Stephen H. Smith wa8lmf (at) aol.com
> EchoLink Node: WA8LMF or 14400 [Think bottom of the 2M band]
> Skype: WA8LMF
> Home Page: http://wa8lmf.com --OR-- http://wa8lmf.net
> World Digipeater Map
> http://wa8lmf.net/APRSmaps
> JavAPRS Filter Port 14580 Guide
> http://wa8lmf.net/aprs/JAVaprsFilters.htm
> "APRS 101" Explanation of APRS Path Selection & Digipeating
> http://wa8lmf.net/DigiPaths
> Updated "Rev H" APRS http://wa8lmf.net/aprs
> Symbols Set for UI-View,
> UIpoint and APRSplus:
> _______________________________________________
> aprssig mailing list
> aprssig at tapr.org
> https://www.tapr.org/cgi-bin/mailman/listinfo/aprssig

More information about the aprssig mailing list